1 Tim 1:15

1:15 The saying is trustworthy and deserving of full acceptance. This expression calls attention to an important point. In the New Testament it is found only in the Pastoral Letters (3:1; 4:9; 2 Tim. 2:11; Titus 3:8).

I am the foremost. Lit. “I am the first.” This is not a characterization of himself prior to his conversion. Rather, as Paul has grown in Christ he has become increasingly aware of his own sinfulness.